WISPIT 2's Second Planet: Catching Formation in the Act

WISPIT 2, a nearby young star with a multiringed protoplanetary disk, already hosted one confirmed planet — a ~4.9 M♃ gas giant sitting 57 au from the star inside a wide disk gap. Astronomers have now confirmed a second, closer-in companion.

The detection combines VLT/SPHERE polarimetric imaging with VLTI/GRAVITY interferometry. The K-band spectrum reveals CO band-head absorption and a continuum shape consistent with a young giant planet. Atmospheric model fitting constrains the effective temperature to 1500–2600 K and the radius to 0.91–2.2 R♃; evolutionary tracks imply a mass of 8–12 M♃ — roughly twice that of the previously known WISPIT 2b.

WISPIT 2 now joins PDS 70 as only the second known system where multiple planets are caught forming inside their natal disk — a rare and direct window into planetary system assembly.